Cell Signaling Technology

Product Pathways - Protein Stability

COPS5 Antibody #6895

Applications Reactivity Sensitivity MW (kDa) Source
W IP IF-IC H M R Mk (X) (Z) (B) (Dg) (Pg) (Hr) Endogenous 37 Rabbit

Applications Key:  W=Western Blotting  IP=Immunoprecipitation  IF-IC=Immunofluorescence (Immunocytochemistry)
Reactivity Key:  H=Human  M=Mouse  R=Rat  Mk=Monkey  X=Xenopus  Z=Zebrafish  B=Bovine  Dg=Dog  Pg=Pig  Hr=Horse
Species cross-reactivity is determined by western blot. Species enclosed in parentheses are predicted to react based on 100% sequence homology.

Protocols

Specificity / Sensitivity

COPS5 Antibody recognizes endogenous levels of total COPS5 protein. This antibody does not cross-react with PSMD14/POH1.

Source / Purification

Polyclonal antibodies are produced by immunizing animals with a synthetic peptide corresponding to residues near the amino-terminus of human COPS5 protein. Antibodies are purified by protein A and peptide affinity chromatography.

Western Blotting

Western Blotting

Western blot analysis of extracts from various cell lines using COPS5 Antibody.

Western Blotting

Western Blotting

Western blot analysis of extracts from 293T cells, either mock-transfected (-) or transfected with a Myc/DDK-tagged human COPS5 cDNA expression construct (+), using COPS5 Antibody.

IF-IC

IF-IC

Confocal immunofluorescent analysis of U-2 OS cells using COPS5 Antibody (green). Blue pseudocolor = DRAQ5® #4084 (fluorescent DNA dye).


Background

The COP9 Signalosome (CSN) is a ubiquitously expressed multiprotein complex that is involved in a vast array of cellular and developmental processes, which is thought to be attributed to its control over the ubiquitin-proteasome pathway. Typically, the CSN is composed of eight highly conserved subunits (CSN1-CSN8), each of which is homologous to one of the eight subunits that form the lid of the 26S proteasome particle, suggesting that these complexes have a common evolutionary ancestor (1). CSN was first identified in Arabidopsis thaliana mutants with a light-grown seedling phenotype when grown in the dark (2-4). The subsequent cloning of the constitutive morphogenesis 9 (cop9) mutant from Arabidopsis thaliana was soon followed by the biochemical purification of the COP9-containing multiprotein complex (4). It is now widely accepted that the CSN directly interacts with cullin-RING ligase (CRL) families of ubiquitin E3 complexes, and that CSN is required for their proper function (5). In addition, CSN may also regulate protein homeostasis through its association with protein kinases and deubiquitinating enzymes. Collectively, these activities position the CSN as a pivotal regulator of the DNA-damage response, cell-cycle control, and gene expression (1).

COPS5/CSN5/Jab1 (c-Jun activation domain-binding protein-1) was originally identified as a transcriptional coactivator of c-Jun and subsequently discovered to be a fifth component and integral part of the CSN (6). As the catalytic center of the CSN, COPS5 is able to integrate multiple functions of the CSN complex such as cell-cycle control, transcription, and DNA-damage response by regulating the activity of CRLs through deneddylation of cullins (7). Indeed, COPS5 harbors a Mpr1-Pad1-N-terminal (MPN) domain with an embedded Jab1/CSN5 MPN domain metalloenzyme (JAMM) motif that is essential for the CSN isopeptidase activity responsible for deneddylation of CRLs. COPS5 is an evolutionarily conserved 38 kDa protein in humans, mice, fission yeast, and plants, which suggests that it is critical to cell survival and proliferation. A role for COPS5 as a positive regulator of cellular proliferation is supported by evidence that it functionally inactivates several key tumor suppressors such as p53, RUNX3, Smad4, and p27Kip1 through altered subcellular localization, degradation, and deneddylation (8-12). These findings are underscored by the observation that COPS5 overexpression has been identified in a number of different tumor types and has been implicated in the initiation and progression of several types of cancer (13). Moreover, COPS5-deficient mice display an embryonically lethal phenotype highlighted by elevated expression of COPS5 targets such as p53 and p27 (14,15).

  1. Wei, N. and Deng, X.W. (2003) Annu Rev Cell Dev Biol 19, 261-86.
  2. Kwok, S.F. et al. (1996) Plant Physiol 110, 731-42.
  3. Wei, N. et al. (1994) Cell 78, 117-24.
  4. Chamovitz, D.A. et al. (1996) Cell 86, 115-21.
  5. Cope, G.A. and Deshaies, R.J. (2003) Cell 114, 663-71.
  6. Claret, F.X. et al. (1996) Nature 383, 453-7.
  7. Wei, N. et al. (2008) Trends Biochem Sci 33, 592-600.
  8. Bech-Otschir, D. et al. (2001) EMBO J 20, 1630-9.
  9. Oh, W. et al. (2006) J Biol Chem 281, 17457-65.
  10. Wan, M. et al. (2002) EMBO Rep 3, 171-6.
  11. Tomoda, K. et al. (2002) J Biol Chem 277, 2302-10.
  12. Kim, J.H. et al. (2009) J Cell Biochem 107, 557-65.
  13. Shackleford, T.J. and Claret, F.X. (2010) Cell Div 5, 26.
  14. Tian, L. et al. (2010) Oncogene 29, 6125-37.
  15. Tomoda, K. et al. (2004) J Biol Chem 279, 43013-8.

Application References

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For Research Use Only. Not For Use In Diagnostic Procedures.

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